Theophylline and various salts thereof are used in the treatment of chronic obstructive airway disease (COAD) and cardiac disease. Major therapeutic effects of theophylline are to relax bronchial smooth muscle and stimulate heart muscle. The major drawback with theophylline therapy is that the drug with a significant frequency produces toxic side-effects; most common are nausea and gastric distress, most serious are convulsions, which may lead to death.
The present invention relates to the treatment of COAD and cardiac disease with xanthine-derivatives which have a favourable ratio between bronchodilator potency and toxic potency compared to theophylline.